Investigate the water potential of celeriac.
Aim Investigate the water potential of celeriac. Apparatus Celeriac - this is the specimen that we will be finding the water potential of. .00 mol dm-3 sucrose solution - this will be placed in the test tube in which the experiment will take place. We will dilute the solution to produce a range of concentrations. 0.0ml Graduated Pipettes (x2) - I had a choice of 5.0ml, 10.0ml and 20.0ml graduated pipettes. I chose this size pipette because it is time efficient and accurate at the same time. It is an accurate piece of equipment because as opposed to standard pipettes, this graduated pipette has 0.1ml graduations to ensure the utmost accuracy. One pipette will be used for water and one will be used for sucrose solution. 250ml Beakers (x2) - these will be used to hold water and the 1.00 mol dm-3 sucrose solution in a safe environment. Cork Borer - this will be used to cut the precise shape of the celeriac. This will also ensure that the surface area to volume ratio is constant throughout the experiment. Razor - this will be used to cut the pieces of celeriac to a precise length. Ruler - this will be used to measure the length of celeriac that will be used in the experiment. Scales - they will be used to measure the mass of celeriac before and after the experiment with accuracy. Therefore, the mass increase/decrease can be calculated after the experiment. These scales
The comparison of antibacterial properties of herbal products and standard antibiotics
The comparison of antibacterial properties of herbal products and standard antibiotics Introduction: This is As biology coursework, studying the area of microbiology the main investigation contains the comparison of antibacterial properties of herbal products and standard antibiotics. Aim: The aim is to investigate the effect of herbal products against standard antibiotics on bacteria growth. To examine the extent to which the herbal products (tea tree oil and peppermint oil) and the standard antibiotics (penicillin and streptomycin), reduce bacteria growth of E.coli and M.luteus. This will be discovered by measuring the growth of bacteria on the agar plates and comparing the results. Background information: The proposed aim surrounds the study of bacteria growth and various other products, which can have an affect on the growth rate; it is therefore necessary to look deeper into the topic criteria to get a wider understanding and to help design an appropriate hypothesis. From self-knowledge antibiotics are chemicals produced by microorganisms, which are designed to inhibit and destroy specific pathogens when used at low temperatures. Antibiotics release chemicals, which inhibit bacterial growth and work on a specific action site. The first founded antibiotic was penicillin discovered accidentally by Alexander Fleming in 1928 from a mold culture. It can be
Sand Dune Succession Coursework
Sand Dune Succession Coursework Aim: The aim of this experiment is to discover how the pH value and the humus value of soil samples collected along a 600 metre transect change as we travel away from the shoreline. The results will indicate how succession has an affect upon the soil and the environment. Also the plant species number will be recorded and a trend will be drawn from the results of percentage cover. Background Summary: Succession is a gradual directional change in an ecosystem over time. A good example of primary succession can be seen on coastal sand dunes such as Winterton sand dunes. Here many stages of succession can be seen in one place. Primary succession is when the starting point is bare ground with no living things present. In this case the starting point is bare sand. The first species to colonise bare ground like this are called pioneer plants. These are able to survive in very difficult conditions and are more salt tolerant than other plants. The sand has very few nutrients and is also unstable. The pioneer plants, examples are sea rocket and sea holly, must be tolerant of salt pray and have xeromorphic features which aid survival in an area with a lack of fresh water in the fast-drying sand. Over many years the environmental conditions become more suitable for a wider range of plants to live. As the number of species increases, competition
"An investigation into the Respiration of Carbohydrate Substrates by Yeast."
AS Biology Coursework 2004. Lucy Nuttney "An investigation into the Respiration of Carbohydrate Substrates by Yeast." Abstract. The investigation considered the reactivity of respiration of three different carbohydrate substrates; glucose, sucrose and starch, by two different sub-species of saccharomyces cerevisiae yeast. The rate of reaction was measured by collecting volumes of gas in a displacement reaction at standardised conditions e.g. time, temperature, pressure, volume of yeast/ sugar. Results showed that glucose produced the most carbon dioxide, followed by sucrose then starch, the biggest difference being between sucrose and starch. Baker's yeast had a slightly higher average than brewer's yeast but it was not considered to be a significant difference and therefore could have been due to chance. It was concluded that both yeasts respire glucose and sucrose at insignificantly different rates but the difference between starch is much larger and therefore much more significant. Pilot Experiment. Before we could test which carbohydrate and type of yeast produced more carbon dioxide, we had to standardise the other variables of this experiment; temperature and concentration. Therefore, in order to find the optimum conditions we carried out a pilot experiment. In this experiment we used a range of temperatures from 10° to 60°C and
Biology coursework planning - the effect of lead chloride on the growth of cress seeds
Biology coursework planning - the effect of lead chloride on the growth of cress seeds Aim: To investigate the effect of different concentrations of a heavy metal chloride, namely lead chloride, on the growth of cress seeds. Introduction: Heavy metals compounds, such as lead chloride are able to dissolve in rain and enter the soils surrounding plants. Some sources of such compounds are exhaust fumes from vehicles, additives in gasoline and paints, fertilisers and mining. Lead chloride is able to accumulate in the soil at sufficient concentrations and is easily absorbed by plants. For plants, lead is a toxin and when present in significant amounts, can cause severe decreases in their growth as well as death. The toxicity of heavy metals is seen as the irregularities in the normal functioning of the plant rather than direct toxicity to plant cells. Symptoms include stunted growth and the yellowing of plants (called chlorosis). Heavy metals collect in different organs of a plant and produce variable effects. Lead disrupts the plant's plasma membrane structure as well as permeability (proteins in the membrane), osmotic balance (the intake of water and ions) and indirectly, plant metabolism (the availability of nutrients for chemical reactions.) These factors are discussed below in further detail. The root cells of a plant carry proteins called chelates in their cell
Can heart disease be prevented?
Can heart disease be prevented? Preventing heart disease. Something our doctors tell us about all the time, something we all want to do, but what exactly is a "heart disease". How can we prevent it if we don't even know what it is? Every one has heard the terms "heart attack" and "stroke" but hardly anyone knows what they mean. Let's start right at the beginning. A heart disease, medically known as cardiovascular disease, is a disease of the heart and the blood vessels. Most people think only the middle aged and elderly get such diseases but no, cardiovascular diseases can be found in children as young as the age of seven years old. This is strongly liked with the children's lack of exercise and a poor diet. There are many types of cardiovascular diseases of which the major ones are atherosclerosis, coronary, rheumatic, congenital, myocarditis, angina and arrhythmia. Heart disease can arise from congenital defects, infection, narrowing of the coronary arteries, high blood pressure, or disturbances. (1) Atherosclerosis is the thickening of the inner layer of the arterial walls due to the deposit of cholesterol, fibrous tissue, dead muscle cells and blood platelets. This deposit is also known as atheromatous plague or an atheroma. Rheumatic heart disease used to be one of the most serious heart diseases in both children and adolescence as it involves damage to the entire
Describe the molecular structure of starch (amylase), glycogen and cellulose, and relate these structures to their functions in living organisms.
Describe the molecular structure of starch (amylase), glycogen and cellulose, and relate these structures to their functions in living organisms. Carbohydrates are the main energy source for the human body. Chemically, carbohydrates are organic molecules in which carbon, hydrogen and oxygen bond together in the ratio: Cx(H2O)y where x and y are whole numbers that differ depending on the specific carbohydrate to which we are referring. Animals (including humans) break down carbohydrates during the process of metabolism to release energy. For example, the chemical metabolism of the sugar glucose is shown below: C6H12O6 + 6 O2 6 CO2 + 6 H2O + energy Animals obtain carbohydrates by eating foods that contain them, for example potatoes, rice, breads, etc. These carbohydrates are manufactured by plants during the process of photosynthesis. Plants harvest energy from sunlight to run the reaction described above in reverse: 6 CO2 + 6 H2O + energy (from sunlight) C6H12O6 + 6 O2 A potato, for example, is primarily a chemical storage system containing glucose molecules manufactured during photosynthesis. In a potato, however, those glucose molecules are bound together in a long chain. As it turns out, there are two types of carbohydrates, the simple sugars and those carbohydrates that are made of long chains of sugars - the complex carbohydrates. In this essay I am going to
Investigation of the effect of different carbohydrate substrates on yeast growth
"Investigation of the effect of different carbohydrate substrates on yeast growth" Yeasts are eukaryotic microorganisms classified in the kingdom Fungi. The cell walls made of Chitin and they can be found virtually everywhere; "on the skin, on some fruits, in the soil and some are airborne" Saccharomyces cerevisiae are the species of yeast to be used in this experiment. They are used in industry due to the secretion of enzymes that they produce which breaks down sugars by two means aerobically or anaerobic. Aerobically (sugar + Oxygen --> Carbon dioxide + Water + 38 ATP energy) and anaerobically (sugar --> Ethanol + Carbon dioxide + 2 ATP) as this experimental investigation is about the growth of yeast, the main equation is the aerobic one due to it provides 38 ATP energy for cell division either by means of mitotic growth (asexual/ budding) which is the more common type of growth or by means of meiosis (sexual reproduction). The energy is necessary for the oxidising the sugar (C6H12O6/ glucose) into pyruvate, glycolysis happens in the cytoplasm. I will experiment three different sugars; glucose a monosaccharide; maltose a disaccharide and sucrose Alternative hypothesis Glucose will have the largest effect on yeast growth. Maltose will have a slight effect on yeast growth. Sucrose will have the least effect on the yeast growth. Null hypothesis (necessary for
An Investigation into the Water Potential Of Root Vegetables.
An Investigation into the Water Potential Of Root Vegetables. The aim of this investigation is to find the water potential of two root vegetables and to evaluate any differences that are found. Root vegetables take in the water they need through a process known as osmosis. Water moves from an area of high water potential to an area of low water potential through a partially permeable membrane. The water potential of root vegetables depends on the concentration of solutes within their cells. Starch is not soluble so the starch content of the vegetables will not affect the water potential. Sucrose however is soluble. In the investigation I will find the isotonic solution for each vegetable based on the principle that when the vegetable is in a hypertonic solution it will lose water (and become plasmolysed) and therefore lose mass and that when the vegetable is in a hypotonic solution it will gain water (and become turgid) and gain mass. By calculating the percentage change in each vegetable piece I will be able to find the concentration of sucrose solution at which the vegetable will gain no mass. Once the isotonic solution is found for each vegetable, its water potential can be found by using a reference graph, which shows the water potential for different concentrations of sucrose. The two vegetables I will use will be a potato and a swede. Swedes are considered a sweet
Biology Coursework - Osmosis - To Investigate concentration of sucrose solution is isotonic to potato cell sap.
Biology Coursework - Osmosis Planning Aim: To investigate what concentration of sucrose solution is isotonic to potato cell sap. Apparatus: 0M sucrose (aq) (distilled water) 2M sucrose (aq) Potato Chip cutter Knife Boiling tubes Measuring cylinder (25cm3) Vernier callipers (to nearest 0.1mm) Balance (to nearest 0.01gram) Safety: I will ensure safety around the lab by: wearing safety goggles, laying paper towels, removing baggage from walking space, push stools under the bench, stand up, walk carefully and slowly - don't rush and handle equipment and apparatus carefully. Preliminary Experiment: I did a small experiment before doing the real one so I could find a suitable range to base my investigation round. I used 3 chips in 3 boiling tubes, each containing 20cm3 of: 0M sucrose, 0.5M sucrose and 1M sucrose. Moles of Sucrose /M Original Mass /g Mass after 3 hours /g Up/Down in mass 0M 8.02 9.94 Up 0.5M 8.18 7.83 Down M 8.83 7.20 Down As you can see from my preliminary results, I should investigate between 0M sucrose and 0.5M sucrose as a suitable range. I predicted that the isotonic concentration lies between 0.35M and 0.4M. Method: I will cut 5 chips with no skin on them and have them approximately the same length, width, breadth and mass (using the balance and Vernier callipers for extra accuracy), then I will dry off the sap completely. I will
